<template>
  <div class="column-detail-page w-690">
    <div class="column-info row mb-4 border-bottom pb-4 align-items-center" v-if="column">
      <div class="col-3 text-center">
        <img :src="column.avatar && column.avatar.fitUrl" :alt="column.title" class="rounded-circle border w-100">
      </div>
      <div class="col-9">
        <h4>{{column.title}}</h4>
        <p class="text-muted">{{column.description}}</p>
      </div>
    </div>
    <post-list :list="list"></post-list>
    <button class="btn btn-outline-primary d-grid gap-2 col-3 mx-auto" @click="loadMorePage" v-if="!isLastPage">
      加载更多
    </button>
  </div>
</template>

<script lang="ts">
import { defineComponent, computed, onMounted, watch, ref } from 'vue'
import { useRoute } from 'vue-router'
import { useStore } from 'vuex'
import { GlobalDataProps, ColumnProps } from '../store'
import PostList from '../components/PostList.vue'
import { addColumnAvatar } from '../helper'
import useLoadMore from '../hooks/useLoadMore'
export default defineComponent({
  components: {
    PostList
  },
  setup() {
    const route = useRoute()
    const store = useStore<GlobalDataProps>()
    // 为了让 computed 响应对应的变化，添加响应式对象
    const currentId = ref(route.params.id)
    onMounted(() => {
      store.dispatch('fetchColumn', currentId.value)
      store.dispatch('fetchPosts', { cid: currentId.value })
    })
    // 检测变化
    watch(
      () => route.params,
      (toParams) => {
        // 确保要变化的路径是进入到用户的专栏
        if ((toParams && toParams.id) === store.state.user.column) {
          // 重新发送请求，在 store 中有对应的缓存设置
          store.dispatch('fetchColumn', toParams.id)
          store.dispatch('fetchPosts', toParams.id)
          // 重新赋值，这样 computed 会变化
          currentId.value = toParams.id
        }
      }
    )
    const column = computed(() => {
      const selectColumn = store.getters.getColumnById(currentId.value) as
        | ColumnProps
        | undefined
      if (selectColumn) {
        addColumnAvatar(selectColumn, 100, 100)
      }
      return selectColumn
    })
    const list = computed(() => store.getters.getPostsByCid(currentId.value))
    const count = computed(() =>
      store.getters.getPostsCountByCid(currentId.value)
    )
    const currentPage = computed(() =>
      store.getters.getPostsCurrentPageByCid(currentId.value)
    )
    const { loadMorePage, isLastPage } = useLoadMore('fetchPosts', count, {
      currentPage: currentPage.value,
      cid: currentId.value
    })
    return {
      column,
      list,
      loadMorePage,
      isLastPage
    }
  }
})
</script>

<style>
.w-690 {
  width: 690px;
  margin: 0 auto;
}
</style>